The present invention relates generally to the measuring of fluid pressure, and more particularly to a method of measuring the peak pressure in liquids and gases, and to an apparatus for carrying out the method.
There are many applications, for instance in combustion engines, in compressors, in pumps or hydraulic systems, where it is important to know the peak pressure of a liquid or a gas, in order to be able to properly dimension various components in dependence upon this peak pressure, to adjust various components in dependence upon this peak pressure and/or to properly control a particular device in dependence upon this peak pressure.
It is known from the prior art to provide an indicator device which uses a metal stylus to scribe onto a specially prepared paper a graph which indicates pressure conditions and fluctuations in a liquid or gas. However, in order to be able to determine the peak pressure it is necessary to read out the diagram which is prepared by this device, since a direct indication of the peak pressure is not provided.
A further prior-art construction, disclosed in German patent No. 1,112,657, does provide for the indication of peak pressure in a fluid. This device operates with a pressure chamber and a one-way valve and indicates the peak pressure by means of a measuring device which for purposes of indicating the peak pressure may be provided with a so-called drag pointer. The basic concept of providing a direct indication of the peak pressure is advantageous in this prior-construction, but it has been found that in the event of rapid pressure fluctuations the device will not operate accurately due to the finite gas volume in the pressure chamber and the masses of the movable parts, so that it can be employed only for measurements within a certain range if accurate results are required.